Molded hair roller

ABSTRACT

Hollow hair roller molded from thermoplastic material, comprises a central ring and two end rings connected to the central ring by peripherally spaced strips, with the diameter of the roller increasing from said central ring toward each end ring.

United States Patent Morane Apr. 9, 1974 MOLDED HAIR ROLLER M21079 3/1964 Buesgen 132/40 .7 v u 1 Invent Bruno 5.638.335 iii??? 2132s a] t. 25133 {73} Assignee: LOrdeal, Paris, France i Filed: June 1972 Primary Examiner-Antonio F. Gulda {21] Am. 259 37 Assistant E.mminerGregory E. McNeill Attorney. Agent, or FirmBrisebois & Kruger [30] Foreign Application Priority Data June 10. 1973 France H 7!.21095 May 3. l97l France .3 7215602 {57} ABSTRACT {52] 0.8. C]. 132139 Hollow hair roller molded from thermoplastic mate- {51] Int. Cl A45d 2/02 rial, comprises a central ring and two end rings con- [5 Field of Search 32/3 42; 2064 46 nected to the central ring by peripherally spaced strips, with the diameter of the roller increasing from {56} References Cited said central ring toward each end ring.

UNlTED STATES PATENTS 2.888.937 6/!959 Weldon 132/33 7 Claims, 5 Drawing Figures PAIENTEDAPR 9 I974 sum 2 Dr 2 FIG. 5

MOLDED HAIR ROLLER SUMMARY OF THE INVENTION Certain hair curling methods involve rolling the hair on rollers consisting of devices having surfaces of revolution formed by rotating a straight or curved line about an axis. When a curved line is used the diameter of the middle of the curler is usually smaller than that of its ends. In order to improve the drying of hair wound up on such rollers an axial hole is usually provided in the roller and transverse orifices are provided in the walls of the roller connecting the axial hole to the ambient space surrounding the roller. These transverse holes are also used to receive pins which are inserted in the roller to hold the locks of hair thereon and prevent its unintentional unwinding.

It should be noted that the number of transverse orifices in the roller is necessarily limited and this leads to two disadvantages: In the first place, the ventilation through each lock of hair wound on the roller is limited, and, in the second place, the insertion of the pins which are to hold the hair on the rollers necessarily involves a certain amount of groping by the user, who must locate with the point of the pin an orifice hidden by the loclt of hair wound on the roller. it should moreover be noted that rollers of this type, when made by molding a thermoplastic material, require a mold having several complicated parts, which considerably increases the cost of the rollers.

It is the purpose of the present invention to provide a roller which may be made by molding thermoplastic material and which has improved means for ventilating and drying the hair wound on the roller and for receiving hair pins which may be inserted in the roller without any need for groping around.

It is accordingly the object of the present invention to provide as a new article of manufacture a generally cylindrical roller having at its midpoint a diameter at most equal to that at its ends, and characterized by the fact that it comprises at its midpoint and at its two ends coaxial rings connected to each other by thin strips which are separated from each other, said strips defining therehetween an internal cylindrical space coaxial with said rings, said internal space having preferably a slight conicity so that it increases in diameter from the ring at the midpoint toward the rings at the two ends.

in a first embodiment, the roller according to the invention comprises two distinct parts connected together at the middle of the roller, each part being defined between two rings, the first of which is hereinafter referred to as the connecting ring and located in the middle of the roller after the two parts of the roller have been connected to each other, and the second of which is hereinafter called the end ring and constitutes one of the ends of the roller according to the invention.

In a preferred form of this first embodiment the two distinct parts of the roller are identical. Each connecting ring carries three tabs regularly spaced about the periphery of the ring, said tabs partially defining a cylindrical surface coaxial with the axis of the rings, carried by the outer wall of said connecting ring, and each extending for about 60 peripherally thereof. The strips which connect the connecting ring and the end ring of one part of the roller are flat strips lying in planes which diametrally intersect the two rings of the part. The strips of each part cover the outer wall of the two rings of that part and are longitudinally terminated by the end planes of the rings of that part, with the tabs of the connecting ring extending beyond the end plane of that ring. The strips of each part of the roller are regularly spaced about the peripheries of the rings of that part and each part is made by molding it from a thermoplastic material. The two parts of the same roller are attached to each other adhesively or by welding the tabs of the connecting ring of the first part to the connecting ring of the other part of the roller.

In a second embodiment the roller according to the invention is made in one piece and is characterized by the fact that the strips of the roller are positioned on opposite sides of the ring in the middle of said roller but do not extend beyond the periphery of the ring and at its outer ends. The strips are connected to the inner peripheral surface of the end rings of the roller, said strips having a substantially trapezoidal section with the smaller base of the trapezoid on the inside of the roller.

In a preferred form of this second embodiment the roller according to the invention is manufactured by molding it from a thermoplastic material. In this case, the central ring is not hollow. That is to say, it comprises a partition separating the roller according to the invention into two sections which form a single integral roller. The roller is symmetrical with respect to the par tition in the central ring. The median plane of each strip passes through the axis of the roller.

It will be seen that the roller according to the invention is extremely useful from the point of view of drying the hair. The hair in a lock is wound on the roller but is in actuai contact with the roller only along stretches having the thickness of the strips of the roller so that ventilation through the lock of hair may take place throughout the length of the roller through the entire space between the strips of said roller. it is obvious that this arrangement provides a substantial improvement over rollers in which the lateral surface has only a few ventilating perforations. Moreover, when it is desired to attach a lock of hair to the roller by means of a pin there is no difficulty in inserting the pin, since this can always find a passage through the roller between two adjacent strips. Even if the pin is not inserted exactly in a diametral plane of the roller, successful insertion is still possible because of the elasticity of the strips of the roller.

It is, moreover, possible to use in combination with the roller according to the invention a pin having two teeth with a space therebetween substantially equal to half the length of the roller. In this case, on the one hand, the lock of hair is more securely attached to the roller than with a pin having a single tooth, and, on the other hand, it is impossible for the user to insert the pin near the connecting ring of the roller, which would prevent its insertion, because each of the two teeth of the pin are necessarily positioned on a part of the roller between the connecting ring and an end ring.

A valuable advantage of the first embodiment of the roller according to the invention relates to the method by which it is manufactured by molding it from thermoplastic material. The inner space defined by the strips is slightly conical so that the mold of a roller part may be made in two parts, one inner and one outer, and the mold opened by separating the two parts from each other axially of the molded roller part.

It will be appreciated that this represents a considerable simplification in molds for rollers, which molds must often comprise complicated parts. This makes it possible to make the parts of the roller very cheaply. Of course, the economic advantage is even greater because the two parts of the roller are identical. These two parts are put together by seating the tabs of the connecting ring of one part in the spaces between the tabs of the connecting ring of the other part until the end planes of the connecting rings of the two parts meet. The two parts may then, preferably, be ultrasonically welded together.

A particularly valuable advantage of the second embodiment of the roller according to the invention is that this roller is produced in a single molding step and in a single piece by positioning inside a two-part mold cores defining the internal space in the roller, which cores are positioned on opposite sides of the partition at the center of the roller. The roller may be removed from the mold quite easily because the two parts of the inner space are slightly conical and the strips of the roller have a trapezoidal section which permits the extraction of the two cores after molding in view of the fact that the end rings of the roller are positioned outside the strips and not inside, as was the case with the first embodiment of the invention. The fact that the roller according to this second embodiment may be produced in a single molding step represents an appreciable economic advantage, since one thus eliminates the step of assembling the two parts of the roller, which is necessary when it is made of two separate pieces.

It is a further object of the present invention to provide a process for assuring the proper positioning of a lock of hair on the roller on which it is wound, said rol ler being of the above-defined type, which method is characterized by the fact that a pin having two teeth is inserted through the lock of hair and the roller. This pin is inserted substantially in a diametral plane of the roller, with the two teeth of the pin passing through the roller between two strips thereof and being spaced from each other by a distance preferably approximating half the length of the roller.

In order that the invention may be better understood, one embodiment thereof will now be described, purely by way of illustration and example, with reference to the accompanying drawings, on which:

FIG. 1 is a perspective view showing one part of the roller according to the invention;

FIG. 2 is an axial sectional view taken through the roller of FIG. 1, with the two parts assembled together;

FIG. 3 is a perspective view showing a roller according to the invention made of two component parts with a lock of hair wound up on this roller and retained thereon by a pin having two teeth;

FIG. 4 is a perspective view showing a roller according to the second embodiment of the invention; and

FIG. 5 is an axial sectional view taken through the roller of FIG. 4.

Referring now to FIGS. 1 to 3 it will be seen that the roller according to the first embodiment of the invention is made of two identical parts each indicated by reference numeral I. Each part 1 comprises an end ring 2 and a connecting ring 3, which are coaxial. The inner and outer diameters of the ring 2 are greater than the inner and outer diameters of the ring 3. Between the rings 2 and 3 are flat strips 4 the planes of which contain the common axis of the rings 2 and 3. Around the rings 2 and 3 are 12 strips 4 regularly distributed at 30 intervals. The strips 4 are longitudinally terminated, that is to say along the axis of the rings 2 and 3, by the end planes of the rings 2 and 3 and they cover the outer walls of the rings 2 and 3. The strips 4 partially define a frustoconical inner space, the smaller diameter of which is adjacent the connecting ring 3. Externally the strips 4 partially define a surface of revolution in which a curved line is revolved about an axis. This surface is smaller in section near the connecting ring 3 than near the end ring 2.

The ring 3 has three connecting tabs 5 on its inner wall in the form of part cylindrical projections having an angular spacing of about 60. The tabs 5 leave therebetween recesses permitting the reception of corresponding tabs 5 on the other member I, the roller according to the invention being formed by assembling the two identical parts 1. In the course ofthis assembly the tabs 5 of one part are inserted between the tabs 5 of the other part and extend along the inner wall of the connecting ring 3 of the part to which they are not attached. These two parts are fixed together by subsequent ultrasonic welding, the tabs 5 of one of the parts being welded to the ring 3 of the other part and the surfaces of the two rings 3 which are in contact being also welded to each other.

It will be seen that the manufacture of the part 1 by molding it from a thermoplastic material is greatly facilitated by the shape of said part. In effect, the inner space defined by the strips 4 is slightly conical, which makes it possible to remove the part of the mold positioned inside the part I. On the other hand, the part of the mold which is positioned outside the part I may be removed by moving it in the opposite direction because of the conicity of the external surface defined by the part I. It will thus be seen that a part 1 may be molded in a two-part mold which is easily opened by relative translation of the two mold parts. This simplification makes it possible to produce the parts 1 very cheaply, and, since the assembly of the two parts I is not very expensive, the final cost of the roller according to the invention is commercially satisfactory.

In order to use a roller according to the invention which has been described a lock of hair 6 is wound on the outer surface of the roller 7 and which comprises the two parts I. When the hair 6 has been wound up on the roller 7 a pin 8 comprising two teeth 8a, 8b is inserted through the roller 7 and the lock of hair 6 which is wound thereon. The pin 8 is inserted in a substantially diametral plane of the roller 7. The user encounters no difficulty in inserting the pin 8 because the teeth 8a, 8b pass through the lock of hair and are inserted between two adjacent strips 4 of the roller 1. It is therefore unnecessary for the user to search for a favorable spot to insert the pin. Moreover, the size of the pin 8 is such that the two teeth 80, 8b, are spaced by a distance substantially equal to half the length of the roller 7. In this case, when the user inserts the pin 8 it is practically impossible for one of the teeth 8 a or 8b to be positioned inadvertently in alignment with the rings 3 of the two parts I and this permits the user to insert the pin 8 through the roller 7 without any preliminary alignment. Moreover the use of such a two-toothed pin ensures a better attachment of the lock ofhair 6 to the roller 7 than does the use of a pin having a single tooth. It should be emphasized that the ventilation of the lock of hair 6 is perfectly assured because of the discontinuous nature of the lateral wall of the roller which permits the passage of air from the inside toward the outside or vice versa through the lock of hair.

Referring now to FlGS. 4 and 5, it will be seen that the roller according to the second embodiment of the invention comprises in its central zone a ring 13 and, at each end, an additional ring. in alignment with the ring 13 is a partition 14 perpendicular to the axis of the roller. The ring 13 and partition 14 constitute a disc which divides the roller into two parts which are symmetrical with respect to the median plane of said disc.

The ring 13 is connected to the end rings 12 by strips which have a length equal to substantially half the length of the roller. The strips 15 have a trapezoidal section the smaller base of the trapezoid being inward of the roller. Twelve strips 15 are thus regularly distrib uted at 30 intervals about the axis of the roller. The strips 15 are positioned symmetrically with respect to the ring 13 without extending beyond the periphery of said ring and they are connected to the end rings 12 along the inner surface of said rings. The inner spaces delimited by said strips IS on opposite sides of the partition 14 are substantially frustoconical, just like the external surface defined by the strips 15.

it will be seen that the embodiment of the roller according to the invention indicated by reference numeral 11 may be molded without difliculty from thermoplastic material, using a mold consisting of two outer halves and two frustoconical inner cores provided with grooves and positioned on opposite sides of the partition l4. The grooves of the core have a trapezoidal section corresponding to the trapezoidal section of the strips 15 and the cores have a generally frustoconical shape corresponding to the shape of the inner spaces defined by the strips 15 on opposite sides of the partition 14. The mold which thus consists of two outer halves and two cores is more complicated than the one required for the first embodiment of the invention, but its price is nevertheless relatively small and its economic value incontestable in view of the fact that it produces a roller made in one piece.

It will, of course, be appreciated that the embodiments hereinbefore described have been given purely by way of illustration and example and may be modified as to detail without thereby departing from the basic principles of the invention.

What is claimed is:

l. Cylindrical hair roller which comprises a ring at each end and two connecting rings at the middle ofthe roller, said rings being coaxial and each end ring being connected to a connecting ring by circumferentially spaced strips which define an internal space having a conicity such that it increases from said connecting rings toward each of said end rings, and said roller comprising two separable parts, each consisting of one end ring, one connecting ring. and the strips connecting said one connecting ring to said one end ring.

2. Ring as claimed in claim 1 in which said two parts are identical.

3. Ring as claimed in claim I in which the connecting ring of each part of the roller carries three connecting tabs regularly distributed about the circumference of said connecting ring, said tabs defining portions ofa cylindrical surface coaxial with the axis of the ring and being carried by an inner wall of said ring and extending peripherally over an arc of about 60.

4. Roller as claimed in claim I in which the strips which connect the connecting ring to the end ring of each part of the roller are flat strips lying in diametral planes bisecting the two rings of that part.

5. Roller as claimed in claim 3 in which the two parts of a single roller are attached to each other by securing the tabs of the connecting ring of the first part to the connecting ring of the other part of the roller.

6. Roller as claimed in claim l in which the strips of each part cover the outer part of the two rings of said part and are longitudinally terminated by the end planes of the two end rings of the part while the tabs of the connecting ring extend beyond the end plane of said connecting ring.

7. Roller as claimed in claim 1 in which the strips of one part of the roller are regularly spaced about the periphery of the rings of the roller.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 802 W3 Dated April 9. 191K Inventrn-(s) BRUNO P. MORAN?! It is certified that error appears in the above-identified patent: and that said Letters iatent are hereby corrected as shown below:

[73] Assignee: L'Oreal, Paris, France [30] Foreign Application Priority Data June 10, 1971 France.

May 3, 1972 France f Signed and sealed this 1st day of 0ctober 1974.

(SEAL) Attest:

MCCOY M. GIBSON JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents USCOMIMDC 6037 5-989 39M PO-IOSD (10-59) a u s. sovimmlm' nmmne orncl: 1 an 0-360-3M 

1. Cylindrical hair roller which comprises a ring at each end and two connecting rings at the middle of the roller, said rings being coaxial and each end ring being connected to a connecting ring by circumferentially spaced strips which define an internal space having a conicity such that it increases from said connecting rings toward each of said end rings, and said roller comprising two separable parts, each consisting of one end ring, one connecting ring, and the strips connecting said one connecting ring to said one end ring.
 2. Ring as claimed in claim 1 in which said two parts are identical.
 3. Ring as claimed in claim 1 in which the connecting ring of each part of the roller carries three connecting tabs regularly distributed about the circumference of said connecting ring, said tabs defining portions of a cylindrical surface coaxial with the axis of the ring and being carried by an inner wall of said ring and extending peripherally over an arc of about 60*.
 4. Roller as claimed in claim 1 in which the strips which connect the connecting ring to the end ring of each part of the roller are flat strips lying in diametral planes bisecting the two rings of that part.
 5. Roller as claimed in claim 3 in which the two parts of a single roller are attached to each other by securing the tabs of the connecting ring of the first part to the connecting ring of the other part of the roller.
 6. Roller as claimed in claim 1 in which the strips of each part cover the outer part of the two rings of said part and are longitudinally terminated by the end planes of the two end rings of the part while the tabs of the connecting ring extend beyond the end plane of said connecting ring.
 7. Roller as claimed in claim 1 in which the strips of one part of the roller are regularly spaced about the periphery of the rings of the roller. 